A sensor has a baked in maximum possible dynamic range determined by the full well capacity and (mainly) the read noise(in modern CMOS sensors). The read noise is an ongoing area of improvement but the latest exmor sony sensor are close to as good as it's going to get.

To achieve the best DR in your files, you need to shoot at base ISO, expose as far to the right as you can without clipping highlights and shoot raw. There's nothing much that can be done to improve on this with standard sensors.

The various flavours of highlight tone priority, Active D lighting etc certainly can't improve on the basic sensor DR. What these systems do achieve is for jpeg shooters. Essentially they map the available DR ad efficiently as possible to the jpeg file. For those shooting RAW, these tricks are of zero use. DR200 and DR400 in full size Fuji files are of no use at all when shooting raw.

If you want to extend DR beyond this, you need a different approach. One approach is HDR: you shoot multiple shots and combine them together either in post processing or in camera. The Fuji superccd in the S3 and S4 goes down a different route. The sensor contains 2 interleaved sets of photosites, one normal sized, the other smaller. A single shot activates both sets of pixels which are then combined in camera to give you a single shot HDR effect.

The EXR sensor is similar to the superccd approach but a little more flexible: you can choose to the use the second sensor pixels to extend the dynamic range or you can use it to increase the pixel count for more detail.

I have an S5 pro and the tech works beautifully. I don't have a great deal of experience with EXR used in this hardware DR expansion mode but all along I have assumed that Fuji know what they are doing and it really does work as well as the S5 superccd.

So, what I am expecting is that if use my X10 in 12MP mode I will get more detail and in 6MP mode I will get 2 stops of extra DR exactly like I get with the S5. I intend to verify this by testing. My initial testing suggests you don't really get that much extra detail when using 12MP mode. It looks to me like the difference between say 6MP and 7 or 8MP, not the full 12MP. It's early days but if this holds up across tests it wil be: 1. Slightly disappointing 2. Mean there is barely any point to the 12MP mode.

I don't know of anyone other than Trevor that doesn't recognize the similarity of how Fuji's S#Pro and EXR sensor's can substantially increase the captured DR, by either one or two stop's worth.

.

Of course, at this point I've done no testing of whether 6MP gives the promised +2 stops of DR.

All my comments refer to raw shooting, I have no interest in jpeg performance as I never shoot jpegs.

Then you'll have to find and use software that presents both sets of RAW data from a single RAF file which you would then examine separately or combine using an HDR technique, because the only easy way to directly get images having expanded DR from the EXR sensor's hardware DR would be to use the EXR camera's JPEG files.

I haven't yet read all of Trevor's replies in the thread but you should also be aware that in the past he has repeatedly denied that EXR sensor's DR hardware technique increases the DR that can be captured in a photo, saying over and over that it's just a "party trick", that the sensor size is what limits the DR that can be captured, completely ignoring the two different exposures that the EXR hardware has to work with. Now he seems to have slightly retreated, calling it a "kludge" instead of a "party trick".

In DPR's reviews of EXR cameras, they've shown examples of how effective the EXR hardware based DR is, yet when Trevor has commented on those examples he denies seeing any significant DR difference. He also has his own technique of measuring DR that unlike every competent review website or recognized expert, doesn't use DR measuring devices like Stouffer's transmission step wedges :

Stouffer has a wide range of wedges that are used in the various industries requiring photosensitive quality control devices. Several sizes and formats are offered to meet most needs.

...

For critical densitometry with traceability, the Stouffer T2120CC and the T1530CC meets and conforms to those needs. Densities of the T2120CC and T1530CC compare with those of a National Institute of Standards and Technology (NIST) Standard Reference Material No. 38120C Step Tablet by means of a densitometer that conforms to conditions specified in American National Standards Diffuse Transmission Densiy A.N.S.I. PH2. 19-1986. There is also the Stouffer XT1725CC step wedge produced on X-Ray film which conforms to NIST No. 38100C.

When making his own DR measurements does Trevor use step wedges as DPR does in its reviews or a different technique used by any other recognized experts? No, his technique is based on taking pictures of bright white clouds. Ask him about it.